Question

Copper reacts with oxygen to make copper oxide.

a) Cu + O₂ → CuO
b) CuO + O₂ → Cu
c) Cu + H₂O → CuO + H₂
d) Cu + O₂ → Cu + O

Potassium reacts with water to make hydrogen and potassium hydroxide.
a) K + H₂O → H + KOH
b) K + O₂ → H₂O + KOH
c) K + H₂O → H₂ + KOH
d) K + H₂O → H₂O + KOH

Magnesium reacts with hydrochloric acid to make magnesium chloride and hydrogen.
a) Mg + HCl → MgCl₂ + H₂
b) MgCl₂ + H₂O → Mg + HCl
c) Mg + H₂ → MgCl₂ + HCl
d) Mg + HCl → Mg + H₂

Answer 1

The correct chemical reaction equations for the given substances are Cu + O₂ → CuO for copper and oxygen, K + H₂O → H₂ + KOH for potassium and water, and Mg + 2HCl → MgCl₂ + H₂ for magnesium and hydrochloric acid.

Step-by-step explanation:

Chemical Reaction Equations

The student asked about the chemical reaction equations for various substances interacting. The correct equations are:

Copper reacts with oxygen to form copper (II) oxide, and the correct equation is Cu + O₂ → CuO.

Potassium reacts with water to produce hydrogen gas and potassium hydroxide, and the correct equation is K + H₂O → H₂ + KOH.

Magnesium reacts with hydrochloric acid yielding magnesium chloride and hydrogen gas, and the correct equation is Mg + 2HCl → MgCl₂ + H₂.

These reactions showcase various types of chemical reactions, including synthesis, single replacement, and combustion, essentially important in understanding the principles of stoichiometry and reaction mechanics in chemistry.